Portable display terminals have become increasingly popular along with the development of communication, semiconductor, and optics technologies, and thus have altered our living environment, and also transformed our sciences and technologies.
The “hard screen” as the portable display terminals have become matured display technologies. There are ongoing and intensive researches on the “soft screen” technologies which are more portable and convenient than the “hard screen”. At present, flexible display devices in the market are still predominated by Organic Light-Emitting Diode (OLED) display and Electrophoresis Display (EPD), where the EPD products in the market are currently limited to static electronic books due to their low response speed, full chromatic aberration, and other technological problems; and the OLED displays have become predominant among the existing flexible display products due to their self-luminescence, high response speed, wide angle of view, high definition, high brightness, high robustness against bending, low power consumption, and other advantages.
The existing flexible display devices include wound flexible display devices, folded flexible display devices, etc., and generally their display screens are wound or folded into their interiors to protect the screens, and to make it portable; and since the existing flexible display devices can display an image only after their screens are spread, the screens have to be folded and spread so frequently that they may be easily damaged, and thus typically have a shorter service lifetime.